My pick of the greatest quotes in history:
"Peace cannot be kept by force; it can only be achieved by understanding." - Albert Einstein
"You must be the change you wish to see in the world." - Mahatma Gandhi
"That which doesn't kill us makes us stronger." - Friedrich Nietzsche
"Ignorance, the root and the stem of every evil." - Plato
"There never was a good war or a bad peace." - Benjamin Franklin
"The only thing we have to fear is fear itself." - Franklin D. Roosevelt
"Never leave that till tomorrow which you can do today." - Benjamin Franklin
"I know not with what weapons World War III will be fought, but World War IV will be fought with sticks and stones." - Albert Einstein
"Somewhere, something incredible is waiting to be known." - Carl Sagan
"We must learn to live together as brothers or perish together as fools." - Martin Luther King Jr.
"The greatest barrier to success is the fear of failure." - Sven Goran Eriksson
Any other great quotes you'd like to add to this list?